A visible–extended shortwave infrared indium gallium arsenide (InGaAs) focal plane array (FPA) detector is the ideal choice for reducing the size, weight and power (SWaP) of infrared imaging systems, especially in low-light night vision and other fields that require simultaneous visible and near-infrared light detection. However, the lower quantum efficiency in the visible band has limited the extensive application of the visible–extended InGaAs FPA. Recently, a novel optical metasurface has been considered a solution for a high-performance semiconductor photoelectric device due to its highly controllable property of electromagnetic wave manipulation. Broadband Mie resonator arrays, such as nanocones and nanopillars designed with FDTD methods, were integrated on a back-illuminated InGaAs FPA as an AR metasurface. The visible–extended InGaAs detector was fabricated using substrate removal technology. The nanostructures integrated into the Vis-SWIR InGaAs detectors could realize a 10–20% enhanced quantum efficiency and an 18.8% higher FPA response throughout the wavelength range of 500–1700 nm. Compared with the traditional AR coating, nanostructure integration has advantages, such as broadband high responsivity and omnidirection antireflection, as a promising route for future Vis-SWIR InGaAs detectors with higher image quality.

We investigate surface passivation effects of SiN_x films deposited by inductive coupled plasma chemical vapor deposition (ICPCVD) and plasma enhanced chemical vapor deposition (PECVD) technologies for InAlAs/InGaAs/InP photo-detectors. It is found that ICPCVD deposited SiN_x film effectively reduces the densities of the interface states and slow traps near SiN_x/InAlAs interface, which realize the small surface recombination velocity and low surface current for InAlAs/InGaAs/InP photo-detectors. By comparing C-V and XPS results, it is suggested that the trap density reduction by ICPCVD technology could be attributed to the disorder suppression on InAlAs surface due to the high density of SiN_x film and less processing energy to the InAlAs surface.

We report on the fabrication of a ${160} \times {120}$ visible (Vis)-extended InGaAs/InP focal plane array (FPA) by means of the inductively coupled plasma etching. Compared to the conventional Vis-InGaAs FPAs, higher quantum efficiency in the Vis spectrum has been achieved. High precision thinning of the $n$-type InP contact layer down to 10 nm has led to quantum efficiencies higher than 60% over a broad wavelength range of 500–1700 nm. Benefiting from the textured surface after plasma etching, 17% lower reflectance over the entire response range was also found. Enhanced Vis/near-infrared (NIR) laboratory imaging capability has also been demonstrated, which has proved the feasibility of such processes for fabrication of future higher definition Vis/NIR InGaAs imagers.

Shortwave infrared polarization imaging can increase the contrast of the target to the background to improve the detection system’s recognition ability. The division of focal plane polarization indium gallium arsenide (InGaAs) focal plane array (FPA) detector is the ideal choice due to the advantages of compact structure, real-time imaging, and high stability. However, because of the mismatch between nanostructures and photosensitive pixels as well as the crosstalk among the different polarization directions, the currently reported extinction ratio (ER) of superpixel-polarization-integrated detectors cannot meet the needs of high-quality imaging. In this paper, a 1024 × 4 InGaAs FPA detector on-chip integrated with a linear polarization grating (LPG) was realized and tested. The detector displayed good performance throughout the 0.9–1.7 um band, and the ERs at 1064 nm, 1310 nm and 1550 nm reached up to 22:1, 29:1 and 46:1, respectively. For the crosstalk investigation, the optical simulation of the grating-integrated InGaAs pixel was carried out, and the limitation of the ER was calculated. The result showed that the scattering of incident light in the InP substrate led to the crosstalk. Moreover, the deviation of the actual grating morphology from the designed structure caused a further reduction in the ER.

Geiger-mode InGaAsP/InP single photon avalanche photodiode (SPAD) with a low dark count rate (DCR) of 870 Hz at a photon detection efficiency (PDE) of 20% at 1064 nm is achieved for a 40 micron diameter device at −30 °C. Extensively optimized and accurately controlled shallow/deep two-step pn junction and doping profiles are identified to play decisive roles for the performance improvement. While a state-of-the-art specific detectivity of 1.4×10 ¹⁴ cm·Hz ^1/2 /W is realized for the optimized SPAD, a temperature coefficient of the breakdown voltage (V _br ) of 139 mV/K, a dark current of 200 pA at 90%V _br and a timing jitter of 280 ps at 20% PDE are also simultaneously attained. Thermal activation energies of approximate 0.5 eV are observed for both the dark current and the DCR at 253–293 K, indicates the dominant source of dark carriers is the mid-gap defect trapping states-related tunneling in the InGaAsP absorber.